Good and easy software for home renovation project?

We're thinking of renovating a wreck, and it needs a lot of cosmetic work both inside and out. I'm thinking about the exterior particularly - have any of you used a good piece of software to help you visualise how eg new windows or painting the house would make it look? If so it would be a real help if you could recommend something. Many thanks in advance!

doodle app is good for colour washing walls on photos - you could draw in new shape windows too - be easier to do that on a photo rather than CAD it up with sketch up if you just wanted to see quickly what it could look like !

there's interior designer for iPad - that's reasonable - I have a copy for quick sketches ... it doesn't give you ready made layouts as such though ... just the tools too drag and drop stuff in and move stuff about and look at it in plan and 3D mode .